Currently, with the increasing of functions of a terminal, the number of antennas of the terminal is increasing. Antennas of a multi-antenna terminal are generally designed in the following two manners.
Firstly, based on function types of communication modules, antennas for different function modules are designed independently at different locations on the terminal, as shown in FIG. 1. Multiple antennas may exist in one terminal. For example, an LTE mobile phone generally includes a main antenna, a GPS antenna, a BT/WIFI antenna, a diversity antenna, an NFC antenna. A multi-mode terminal may include more antennas. In this case, antennas are arranged on an upper end, a lower end and two sides of the terminal, as shown in FIG. 2. In a case that a few of the antennas are close to one another, performances of the antennas may become poor since strong interference exists between signal transmissions and signal receptions. Therefore, it is difficult to arrange the antennas and give an overall consideration to all the antennas in the limited space inside the terminal, thereby making poor performances of a few of antennas in using the terminal, and affecting user experiences.
Secondly, the antennas for the communication modules are integrated into one antenna by directly adding a filter network and a matching circuit in the terminal. In this case, radio frequency transceiver circuits corresponding to the antennas of the communication modules are needed. The filter network passes a received signal or transmitted signal in an operating frequency band of a respective radio frequency transceiver circuit, while isolates received signals or transmitted signals in operating frequency bands of other radio frequency transceiver circuits, and the matching circuit matches impedances of the antennas with impedances of the radio frequency transceiver circuits, as shown in FIG. 3. This solution can be only applied in combining multiple frequency bands or simply combining GPS and BT/WIFI but can not achieve a multi-mode multi-pass communication, since the antenna is not separated into a transmission antenna and a reception antenna in this solution.
Therefore, it is an urgent issue to be solved that how to reduce interference between multiple antennas and achieve the multi-mode multi-pass communication.